Why AWS Builds Regions Where It Does - The Hidden Criteria Behind Data Center Site Selection
We explain the criteria AWS considers when deciding region locations, including power supply, geopolitical risk, data sovereignty legislation, network connectivity, and natural disaster risk, with concrete examples from specific regions.
Opening a Region Is a Multi-Year Mega-Project
It typically takes 2 to 3 years from announcement to launch for AWS to open a new region. During this period, an enormous process unfolds: land acquisition, power infrastructure development, building construction, network installation, hardware delivery and setup, software deployment, and security certification. Each region consists of a minimum of 3 Availability Zones, and each AZ comprises one or more data centers. In other words, opening a single region is a project that simultaneously constructs at least 3 data center clusters. As of 2024, AWS operates 33 regions and has announced plans for several more. While the investment per region is not publicly disclosed, industry estimates suggest each region requires an investment on the order of several billion dollars. Recouping this massive investment requires sufficient demand in that region as a fundamental prerequisite.
Power - The Largest Cost Factor for Data Centers
Power accounts for 30-40% of data center operating costs. When AWS selects a region location, stable power supply and electricity costs are the most critical criteria. Northern Virginia (us-east-1) is the world's largest data center hub, and this is no coincidence. Virginia has electricity rates below the national average, high supply redundancy from multiple competing power companies, and proximity to Washington, D.C., where federal agencies are concentrated. The Nordic region (Stockholm) benefits from abundant, inexpensive renewable energy from hydroelectric power. Low temperatures also reduce cooling costs, keeping PUE (Power Usage Effectiveness) low. AWS set a goal to power its entire operations with 100% renewable energy by 2025, making renewable energy availability an important factor in region selection. Middle Eastern regions (Bahrain, UAE) have low power costs but high cooling costs. Cooling data centers in environments exceeding 50 degrees Celsius is a technical challenge, and AWS has deployed advanced cooling technologies such as evaporative cooling and liquid immersion cooling.
Data Sovereignty and Compliance - Laws That Create Regions
The biggest driver of recent region openings is data sovereignty legislation in various countries. The EU's GDPR (General Data Protection Regulation) imposes strict conditions on transferring EU citizens' personal data outside the EU. To comply, AWS has deployed 6 regions within the EU: Frankfurt, Ireland, Paris, Milan, Spain, and Zurich. In China, foreign companies are legally prohibited from directly providing cloud services, so AWS operates through Chinese partner companies (Sinnet for the Beijing Region, NWCD for the Ningxia Region). Chinese regions run on infrastructure completely isolated from other regions, with separate AWS accounts. In Southeast Asian countries such as Indonesia, Malaysia, and Thailand, laws mandating domestic storage of government and financial data have been enacted in succession, and AWS has opened regions in these countries. Data sovereignty legislation is trending toward further strengthening, and AWS's region expansion is accelerating in response to these legal requirements.
Natural Disaster Risk and Physical Separation of AZs
When AWS designs AZs, natural disaster risk assessment is conducted in extreme detail. AZs within the same region are geographically distributed so that a single natural disaster cannot simultaneously affect multiple AZs. Specifically, AZs are separated by tens of kilometers or more, but placed within a range where network latency stays below 2ms. This precise distance design of "far enough apart, yet close enough" enables both fault tolerance and low latency. The Tokyo Region (ap-northeast-1) is designed with Japan's earthquake-prone nature in mind. Each AZ is placed on different geological conditions, and buildings are constructed to standards exceeding Japan's seismic codes. During the 2011 Great East Japan Earthquake, the Tokyo Region continued operating without significant damage. Flood risk is also an important consideration. Data centers are built away from river floodplains, and power and communication equipment is placed on upper floors as a precaution against flooding. During the major European floods of 2021, some cloud providers' data centers were affected, but AWS's European regions were not impacted.
Network Connectivity and Submarine Cables
A region's value is determined by how quickly it can be accessed. AWS invests in and lays its own submarine cables, connecting regions via dedicated high-bandwidth networks. When selecting locations for new regions, proximity to existing submarine cable landing points is an important factor. The Singapore Region functions as a Southeast Asian hub because Singapore is one of the world's premier submarine cable hubs, with high-speed connectivity to virtually every country in the Asia-Pacific region. Similarly, the Ireland Region is near major European landing points for transatlantic submarine cables, functioning as a hub for traffic between North America and Europe. AWS combines CloudFront's 600+ edge locations with Global Accelerator's Anycast IPs to provide low-latency access even to users far from regions. Region site selection is not simply about deciding where to build a data center but a strategic decision that considers optimization of the entire global network. For a deeper understanding of cloud infrastructure design philosophy, specialized books on Amazon can be helpful.